Grand Theft Auto Vice City Walkthrough
CabMageddon

You have to go pick up Mercedes. No sign of Mercedes. Instead, six rival cabs show up. You have to stay alive for a minute. In essence just drive fast around the outside to dodge them.

Now (vrooom vrooom) the Evil Zebra Cab shows up. VERY cool design! Blast him and ram him until he's dead.

Taxi firm asset completed.

$5000 earnings - collect regularly at the dollar sign.

Payoff: $5000

Plus you get a samurai sword from leader

Now there's a zebra cab in your cab shop!!

Tip from The An0nym0us Artist
You just need, after getting to the Pink spot and get faster to the left side near the water and jump on the boarder to finally go where there's a crated wall and wait the whole minute there and when the Zebra Cab will appear, just stay there! He will ram himself on the wall and burn.. Just wait till the katana guy will be near of you and kick him in the water :)

Tip from MTHWrestler:
Once you have evaded the other cars, and you are up against the evil taxi... All you have to do is get him to ram his car against somewhere while you are outside of your car, and then steal his car and run him over with it.

Tip from Lubi23:
when doing the last taxi mission just weave in and out of the pillers until the time runs out and use the rocket launcher to blast the zibra taxi that it $5000.00